Belt shifter



Nov. 18, 1941. G. l.. GARVIN BELT SHIFTER `4 sheets-sheet 1 Filed June 28,. 1940 Nov. 18, 1941.

G. l.. GRVIN BELT'SHIFTER Filed June 2s, 1940 4 Sheets-Sheet 2 v4 INV'bNl OR. 650265 ey//vI ATTORNEY'.

G. L. GARVIN BELT SHIFTER Nov. 18, 1941.

Filed June 28, 1940 4 Sheets-Sheet 3 I I l Il IN VENTOR. 64E/m4 BY -mmw/ TTORNEY5.

Nov. 18, 1941. G. L. GARVIN 2,263,438

BELT SHIFTER Filed June 28, 1940 4 Sheets-Sheet 4 @M/Wo ATTORNEYS.

set.

Patented Nov. 18, 1941 BELT SHIFTER f George L. Garvin, South Bend, Ind., assignor to South Bend Lathe Works, South Bend, Ind.,

a corporation of Indiana Application June 2s, 1940, serial Nb, 51.12.862

9 Claims.

countered in attempting to shift V-belts has been the fact that the pulleys therefor are anged, and that the driving force is effected by engagement between the sides of the V-belt and the inner` faces of the pulley flanges, with the belt seating within the V-pulley in a manner to prevent lateral displacement thereof. Hence when one of the respective step pulleys is shifted toward the otherV to loosen the V-belt, the movement must be of substantial amplitude for the belt to clear the pulley iianges and to ride over the flanges of both of thepulleys to which ythe belt is to be changed. This means that the belt is shifted bodily with respect to both' pulleys, Vso that some external means is necessary to confine it and maintain it in position to be re- Also, a V-belt will normally take a circular position, so reducing the spacing between centers, of pulleys normally results merely in outwardl bowing of the belt between the pulleys with at least a portion thereof remaining in the grooves of the V-pulleys.

It is the primary object of this inventionto provide `means for overcoming these difficulties and solving the problem of shifting a V-belt in a ycontrolled manner from one step of a step pulley to any other selected step of said pulley.

A further object of this invention is to providev a device of this character having means for shifting one of a pair of step pulleys, together with means for enveloping and coni-lning the V-belt in accurate desired position released from and clear of the opposed step pulleys.

A further object is to provide a belt shifter having means for releasing a belt from a pair of complementary step pulleys, means for holding the belt in controlled position clear of said pulleys, and means for shifting said last named A further object is to provide a device of this character having a stationary and a shiftable step pulley, with a belt retaining envelope comprising a pair of normally spaced parts, said envelope including one portion which is shiftable with the shiftable step pulley to a position adjacent to the other part of the envelope for closing said envelope.

A furtherobject is to provide a device of this character with a normally open multi-part belt retaining envelope having one part shiftable with a shiftable step pulley between open and closed positions, said envelope havingk an interior perimetral dimension when closed which is substantially equal to the outer peripheral dimension of a belt, whereby, when said envelope is closed, a V-belt will be confined in said envelope clear of said step pulleys'by virtue of the natural tendency of avv-belt to assume a circular shape when released from tension.

A further object is to provide a novel. simple, and comparatively inexpensive device of this character which is positive and trouble-free in operation.

A further object is to provide a device of this character which is adapted for operation and control from a control station remote therefrom.

Other objects will be apparent from the description and appended claims.

In the drawings:

Fig. 1 is a view of the device in front elevation.

Fig. 2 is a view of the device in side elevation.

Fig. 3 is a View ofr the device in front elevation in belt releasing position with parts shown in section. j

Fig. 4 isa side elevation of the device in belt releasing positionwith parts broken away.

Fig. 5 is a fragmentary side elevation of the device illustrating the belt shifter in another position. 'I

Fig. 6 is a side elevation of the device with Vparts shown in section illustrating the belt in changed driving relation to the pulleys. l

Fig. 7 is a transverse horizontal sectional view of the device taken o n line 1-1 of Fig. 1.

Fig. 8 is a transverse horizontal sectional View of the device taken on line 8-8 of Fig. l.

Fig. 9 is a sectional view similar to Fig. 8, but illustrating the application of the device to the use of double V-belts.

Fig. 10 is an enlarged detail sectional view taken on line IIJ-I0 of Fig. 2.

Fig. 1lA is a fragmentary front elevational view of the device provided with control means operable from a remote point.

Fig. 12 is a fragmentary view of the device with remote control means taken in side elevation, and with parts broken away.

Fig. 13 is a fragmentary rear elevation of a portion of the device including the remote control mechanism.

Referring to the drawings which illustrate the preferred embodiment of the invention, the numeral 26 designates a suitable base upon which the device is adapted to be supported. Mounted upon this base 2|! is an upright guide member 2|. A second upright guide member 22 extends parallel to guide member 2| in spaced relation thereto and is secured thereto by bolts 2'3 extending through spacers 24 positioned between said guide members in spaced relation along the height of said guide members 2| and 22. The guide members are preferably elongated flat bars of substantial width. As best illustrated in Fig. l, the guide member 2| extends above the height of the guide member 22.

At a position between the upper ends of the guide members a suitable bearing 25, constituting a spacer for said guide members, is secured to said guide members by securing members 26. i

Bearing 25 has a sleeve 21 projecting therefrom and journals a horizontal shaft 28 passing centrally between the guide members 2| and 22. The rear end of shaft 28 mounts a suitable V-pulley 29 for a V-belt 30 which extends to the drive means for the device. Upon the opposite end of the shaft 28 is mounted a step pulley comprising a plurality of V-pulleys 3|, 32, 33 and 34, of progressively increasing size from outer to inner end, with the inner face of the innermost pulley 34 spaced slightly forwardly from the front vertical edges of the guides 2| and 22.

In spaced relation below the bearing 25, a bearing 35 is slidably mounted between the guides 2| and 22. Bearing 35 is retained against lateral movement on theguide members by means of end plates 36 and 31. Bearing 35 mounts a sleeve 38 which projects rearwardly therefrom and journals a shaft 4| which mounts a pulley 39v over which is adapted to run an upwardly directed belt 4|) extending to the work to be driven by the device. The forward end of shaft 4| mounts a series of V-pulleys 42, 43, 44 and 45, whose ilanges are aligned with the flanges of pulleys 3| to 34 respectively. Pulleys 42-45 are of decreasing size from outer to inner end, with the difference in the size thereof being complementary to the difference in the size of the pulleys 3|34.

A spacer member 46 connects the upper ends of the guides 2|, 22, and a horizontal guide pin 41 is xedly carried by spacer 46 and projects therefromat its ends. Il'he guide pin 41'has a plurality of recesses 48 formed in equi-spaced relation along its length at its forwardly projecting end for purposes. to be hereinafter set forth. A sleeve 49 is rotatably mounted upon the rear end of pin 41 and has xedly connected thereto anoperating arm 50. A link 5| is also xedly connected with the sleeve 49 and with lever 50, and extends downwardly therefrom. Link 5| is provided with a cut-out 5| adapted to fit freely around the shaft 28. At its lower end the link 5| is pivotally connected with a screw threaded member 52 by means of bolt 53. A turn buckle 54 is threaded on thelcwer end of member 52, and a second threaded member 55 is threaded in the opposite end of the turn buckle and is pivotally connected with the end plate 36 of the bearing 35 by bolt 56.v

It will be seen that the link 5| constitutes one part, and members 52 and 55 constitute the other part of a toggle member whose center pivot is member 53. Hence, When the lever is lifted upwardly from the position illustrated in Fig. 1 to the position illustrated in Fig. 3, the link 5| will be pivoted about the pin 41 to an angular position with respect to the vertical which raises and pivots the other toggle part 52-55 to raise the bearing block 35 guided by the guides 2|, 22. In this way the pulley 39 and the step pulley 42-45 are both raised to release the respective belts trained thereover.

A block 51 is rigidly secured between the guides 2|, 22 at the lower end thereof and rigidly mounts a second guide pin 58 parallel to the pin 41. A sleeve 59 is slidably mounted on pin 58, and a sleeve 60 is slidably mounted upon pin 41. These sleeves 59, 66 have rigidly connected thereto a rigid rectangular frame member comprising horizontal upper and lower horizontal bars 6| and a pair of spaced vertical bars 62. Racks 63 are rigidly carried by the upper and lower ends of the frame 6|-62 to extend parallel to the pins 41-58. These racks mesh with gear segments 64 xedly mounted on a vertical shaft 65 which is journaled in bearings66 carried by guide 22. At the upper end thereof the shaft mounts a suitable operating lever 61.

Hence it will be seen that When the lever 61 is operated, the shaft 65 rotates to rotate the gears 64 and longitudinally shift the racks 63 for movement of the frame 6|-62 upon the guide pins 41-58. As best illustrated in Fig. 10, the upper frame member 6| carries a block 68 adjacent pin 41 having a bore 69 therein extending transversely of pin 41. Bore 69 receives a coil spring 10 whose outer end bears .upon a set screw 1| threaded in block 68. The opposite end of the bore 69 terminates adjacent the sleeve 60, which has a passage 12 therein registering with bore 69 for reception of a ball 13 pressed upon by spring 16. The ball 13 normally seats within one of the recesses 48 of the pin 41 for the purpose of accurately positioning the frame 6|-62.

A V-belt 14 is normally trained about complementary steps of the step pulleys 3|, 34, 42-45, and the portion thereof adjacent the upper step pulley 3l--34 passes through a part of a retainer or envelope fixedly carried by the upper part of the frame 6|-62. This envelope portion comprises front and back walls 15 which have openings 16 therethrough concentric with the shaft 28 and of a diameter slightly larger than the diameter of the largest pulley 34 of the upper step pulley. The envelope portion also has end walls 11 of a width such that the inner faces of thewalls 15 are spaced apart a distance slightly greater than the maximum transverse dimension of the belt 14. The side walls 11 of the envelope merge in a rounded portion 18 concentric with lshaft 28 at the upper end of the envelope. 'Ihe lower ends of the front and back plates 15 of the envelope portion are provided with semi-circular recessed edges 19 of the same diameter as the openings 16.

A lower envelope portion 88 is slidably mounted upon studs 8| parallel to studs 41--58. Shafts 8| are carried by the lower enlarged end portion 82 of end plate 31 of bearing 35. The envelope portion is provided with vertical guide flanges 83 seating on the inner vertical edges of the upright frame members 62 for sliding movement thereon. The guide member 80 has a. channel shaped portion 84 of the same width as the'upper portion of the envelope, Vand is .of semi- .circular form concentric with shaft 4|. 'The inner Adiameter of channel .portion 84 is .slightly larger than the diameter of the largest pulley `42 of the lower step pulley 542-45.

The operation of .the device Lis as follows: Figs. l and 2 illustrate'the operative driving position of the device, with ithe drive belt 1'4 seated .in and tensioned on complementary steps of `.the two step pulleys to impart driving rotation from the :drive shaft 23 to `the driven shaft 4|. Assuming that it is desired to .shift the fbelt from onesto another position on said step pulleys for the purpose of changing the speed of the driven shaft 4|, the lever 50 is rst raised to the position illustrated in Figs. .3 and 4. Infthis position, the itoggle 5|, 52,:55 has been pivoted to raise the bearing 235 journaling the shaft -4-l. At the Isame time the lower envelope portion Bil and the studs 8|, both carried by bearing v35, are also raised an equal amount. The parts ar-e so proportioned and arranged that when the 'lever 50 reaches the upper limit of its movement, the upper edge of the lower envelope port-ion 80 will 'be brought sub-- stan-tially into engagement with the lower edge of the envelope 1-5, 'il to close said sectional envelope. Also, it will -be observed that in this -closed envelope position the semi-circular edge portions H9- '84 vof the upper and lower envelope portions, respectively, are positioned in substantially circular relation ias bestillu-strated in Fig. 3.

By virtue of the cross sectional configuration of a V-belt, the same has a tendency :to assume circular shape when lreleased from tension.

Hence, as the tension on the belt 'i4 is released by the raising of the shaft 4| and associated parts, the belt 14 will first tend to expand laterally and Yinto engagement with the sides Tl of the stationary portion of the envelope, and thereafter as the vertical upward Ymovement of the shaft 4| and vassociated parts is continued, the belt will tend to .assume-the shape `of the closing `envelope until -it bears 'completely against the envelope at walls l?, 'i8 and l|34 thereof throughout its entire outerperiphery when the envelope is fully the belt 'I4 thereof will be fully Aconfined within the closed envelope and will be prevented from lateral movement with respect to the step pulleys 3ft, 45 from which it vhas just been released, as illustrated in Fig. 2 and Fig. 4. lThe elongation of the upper part of the envelope `at the walls l5 obviously prevents the lateral displacement of the belt 14 during the interval between initial belt releasing movement and complete closing of the envelope7 at which time the belt assumes the position illustrated in Fig. 3.

It will be observed from Fig. 3 that the dimension of the parts is such that the inner circumference of the belt 14 at the upper and lower bends thereof is greater than the circumference of the largest step pulleys 313 and 42 of the upper and lower step pulleys. Hence the Vbelt is confined in a position whereby the lever 6l may be swung to any desired position. As illustrated in Fig. 5, this .lever may be swung to shift the envelope upon the pins lll-'58 to outermost position in register with the outermost pulleys 3=|i|2 fof the Itwo step pulleys. For the pur- .pose Yof assuring accuracy of positioning, it will be observed that, as the frame 62 and the envelope carried thereby lare shifted, by Voperation of the lever Bl, the ball ,'13 will seat successively in the recesses 48 of the pin 4l, and by this means the voperator is enabled to tell vwhen he has reached the `precise position desired for the 4particular belt setting which he is selecting. 4

Therefore, when the -ballS seats in the desired recess 48, movement .of the lever -61 is stopped and thereupon the lever 50 .is shifted .downwardly to expand the 'toggle 5|, 52, 55 to the Aposition illustrated in Figs. 1 and 6, thereby lowering the shaft 4| to a Vpoint where the 4beltis tensioned upon the `pulleys :3i-t2 and is in position for driving said pulley and the shaft 1li.

From the Vabove it Will be seen that the device is simple in its operation since itrequires only the manipulation of two levers -50 and -61 in `proper sequence. The loosened belt i4 is fully confined and prevented from displacement from alignmentv with the pulleys from which it has just been released. The desired setting of the envelope may be quickly and accurately made guided by the impulses imparted bythe seating .of the spring pressed ball f1.3 in recesses t8 when the envelope has reached a position in register with any one of the steps of the step pulley.

The device is not limited to the utilization of a single pulley but may, as illustrated in Fig. 9, be used for application Ito constructions where multiple belts 7M are required for the transmisrsion of -a -greater amount of power than a single belt can transmit. For this purpose vthe envelope is vconstructed as above illustrated, with the exception that it is-of a width to receive two bel-ts side by side therein, Yand is provided at the center of its inte-rior with a-guide ridge 98, for properly spacing said belts to permit their automatic re-seating upon the ydouble pulleys Sil or 92 after the lenvelope has been shifted into register therewith.

In the event it is desired to control the operationof the mechanism as described above from a vremote point, mechanism for that purpose, as Vbestillustrated in Figs. ll to 13 inclusive, may be employed. The shaft 65 has mounted on its upper end a socket lliil which is connected by a suitable link |G| with a shaft |532 extending to the remote control station, said shaft |2 having a socket I B3 of a rconstruction complementary to socket itil. The parts itil, lill and :It are pivotally interconnected to constitute a universal joint, whereby rotation fof the shaft l|il2 at the control station will equally rotate the shaft 65. A shaft IM may valso Iextend from the 4control station, and mounts at its end a socket |65 connected with a link |55 in turn connected With a socket |31 for the purpose of vcontrolling means for raising and lowering the pulley shaft 4|. Sockets |05, .|96 and lill are pivotally y-interconnected to constitute a universal joint for transmitting -to a shaft il@ mounting socket lill the rotation imparted to the control shaft M24. Shaft H28 is journaled in the guide 22 and mounts thereon a lever |39.

A pair of vertically spaced bolts iii? .extend centrally between the guides 2| and v22 below the bearing 25, and seat in vertical notches v| of a block H2 positioned between the guides 2| and 22. A bearing H3 .is mounted in the vblock ||2 and journals a shaft l i4 parallel to shaft 28 and positioned therebelow. At the front end of the shaft H4 is mounted a V-pulley H5 adapted to be driven by a. belt II6 which also runs over a pulley I I1 mounted upon the shaft 28 between the front edge of the frame parts 2|, 22 and the adjacent step pulley 3I-34. Hence it will be observed that the shaft H4 is constantly rotating.

Adjacent the upper and lower ends of the block H2 are provided guide passages H8 in which pins H9 are slidable. Pins H9 are pivotally connected at with the ends of the lever |09. Each of these pins H9 has a projection |2| in the nature of a cam projecting from. its outer end. The lever |09 swings between limits which normally positions one of the pins H9 retracted and the other pin H9 extended, as best illustrated in Fig. 12 where the lower pin is retracted and the upper pin is extended. It will be understood that the position of the lever will be shifted to reverse the parts which are retracted and extended by rotating shaft |08. Spaced downwardly from the upper pin H9 is a recess |22 receiving a spring |23 which presses outwardly upon a ball |24. A fly wheel |26 is journaled upon the bearing I I3 at the rear thereof and has a pair of diametrically opposed recesses |25 formed in its inner face. Ball |24 is normally spring pressed into one of the recesses |25. At one point in its periphery, preferably'radially aligned with recesses |25, the fly wheel |26 is provided with a radial socket in which is slidably mounted a pin |21. Pin |21 has a reduced neck portion |28 and a head |29. An endless coil spring |30 seats in a notch in head |29 and in a groove formed in the fly wheel, and serves to provide means for normally urging the pin |21 radially inwardly. As illustrated in Fig. 12, the cam projection |2| of one of the pins H9 is normally seated under the head |29 to hold the pin |21 in its outermost position. The outer face of fly wheel |25 is concentrically recessed, and the inner end of pin |21 extends to said recess when the projection |2| seats under the head |29 of said pin |21.

Fixedly mounted upon the shaft I I4 Within the recess formed in the outer face of the ily Wheel |26 is a rotating disk I3| which has a plurality of notches |32 positioned in equi-spaced relation therearound.

A link |33 is pivoted by a pin |34 to the fly wheel |26, and at its lower end is pivoted at |35 to the lower bearing 35 which mounts shaft 4I.

The parts are illustrated in Fig. l2 in their normal or rest position with the bearing 35 positioned at its belt tensioning or lowermost position. If it is desired to release the belt tension, the shaft |04 is rotated to thereby rotate shaft |08. The rotation of shaft |08 pivots lever |09 from the position illustrated in Fig. l2 to the opposite position thereof to retract the uppermost pin H9 and to extend the lowermost pin H9. The retraction of the uppermost pin I |9 permits the spring |30 to urge the pin |21 inwardly against the periphery of disk I3I so` that it may seat in the first notch of the constantly rotating disk |32 which registers therewith. The seating of pin |21 in said notch provides/a driving connection between the constantly/ rotating disk I3I and the fly wheel |26. The subsequent rotation of the y wheel |26 serves to shift the link |33 to raise the upper end thereof to a belt releasing position as will be understood. As the disk approaches belt releasing position, which is displaced 180 degrees/from its initial position, the

cam projection |2| of the lowermost pin H9 seats under the head |29 to urge the pin |21 radially outwardly for release thereof from notch |32. This occurs slightly before the lowermost recess I 25 in the fly wheel comes opposite the spring pressed ball |24, so that when a. full half revolution of the ily wheel has occurred, the ball |24 will press into the adjacent fly wheel recess |25 to stop the ily wheel at a position exactly degrees from the starting position. In this way it will be observed that the belt tension upon drive belt 14 may be released by operation of a control extending to a point remote from the device.

Thereupon the shaft |02 may be rotated to shift the envelope for belt 14 to desired position relative to the step pulleys, and then the shaft |04 at the control station may be again rotated to return the lever |09 to the position illustrated in Fig. 12. Thereupon the lowermost pin I I9 is retracted to permit the pin |21 to seat in a notch |32 in constantly rotating disk |3| for effecting driving connection between the fly wheel |26 and said disk I3I, which rotation is limited to 180 degrees to position the parts as illustrated in Fig. 12, by virtue of the release of pin |21 by the cam projection |2| of the upper pin H9 as will be obvious. This constitutes a simple and effective means for controlling the belt shifter from a remote station, and has the advantage of simplicity, inexpensive construction, and positive mechanical operation.

I claim:

1. The combination with a support mounting a pair of complementary flanged step pulleys interconnected by a V-belt, wherein at least one of said pulleys is shiftable on said support between belt tensioning and belt releasing positions, of means for shifting said belt between selected steps of said pulleys comprising a guide on said support parallel to the axes of said pulleys, a frame shiftable on said guide and arranged parallel rto the plane of said belt, and a two part belt confining member carried by said frame, one part of said confining member being fixed on said frame and the other part being slidable on said frame and means connecting said shiftable confining member with said shiftable pulley, the parts of said confining member being positioned adjacent each other in belt releasing position to constitute a unit in which said belt nests clear of said pulleys to accommodate shifting of said frame and confining member to any selected position relative to said pulleys and guide.

2. A belt shifter comprising a support, a pair of spaced complementary flanged step pulleys, means fixed on said support and journaling one pulley, a carrier shiftable on said support for journaling the other pulley, a V-belt connecting said pulleys, a belt retainer juxtaposed to said first pulley and shiftable on said support in a path parallel to the pivot axes of said pulleys, a second belt retainer normally spaced from said first retainer and shiftably mounted on said carrier in a path parallel to the pivot axes of said pulleys, and means for equally shifting both retainers, at least one of said retainers being elongated to extend adjacent to the other retainer when said retainers and pulleys are disposed in belt releasing position, said elongated retainer having openings in its sides concentric with and larger than the largest step of the stationary pulley, and the adjacent ends of said retainers having complementary concave edges to form openings therebetween concentric with and larger than the largest step of the shiftable pulley.

3. The combination with a support, a driving shaft journaled in said support, a step pulley on said shaft, of a carrier shiftable on said support, a driven shaft journaled in said carrier, a step pulley on said driven shaft, a belt trained over said pulleys, a belt retainer juxtaposed tosaid driving pulley and shiitable on said support in a path parallel to the pulley axes, a second belt retainer normally spaced from said rst retainer and juxtaposed to said driven pulley, said second retainer being shiftable on said carrier in a path parallel to the pulley axes, and selectively actuatable means driven by said driving shaft for shifting said carrier to belt releasing position with said second retainer juxtaposed to said first retainer.

4. The combination with a support, a driving shaft journaled in said support, a pulley on said shaft, of a driven shaft, a bearing shiftable on said support toward and from said rst pulley and journaling said driven shaft, a pulley on said driven shaft, a belt trained over said pulleys, and selectively actuatable means on said support driven by said driving shaft for shifting said bearing.

5. The combination dened in claim 4, wherein said selectively actuable means comprises a rotating member driven by said driving shaft, a normally stationary member journaled concentric with rotating member, a link pivoted to said last named member and to said bearing, and normally released clutch means carried by said normally stationary member and engageable with said rotating member.

6. The combination with a support, a driving shaft journaled in said support, a pulley on said shaft, of a carrier shiftable on said support, a driven shaft journaled in said carrier, a pulley on said driven shaft, a belt trained over said pulleys, a normally rotating member journaled in said support and having a driving connection with said driving shaft, a normally stationary rotatable member journaled on said support adjacent and concentric with said normally rotating member, a link pivoted to said last named member and to said carrier, means for effecting a driving connection between said rotating and rotatable members, and means carried by said support for disengaging said driving means upon predetermined rotation of said normally stationary rotatable member.

7. Ihe combination defined in claim 6, and means for stopping rotation of said normally stationary member in predetermined position after operation of said disengaging means.

8. The combination dened in claim 6, wherein said normally stationary member is recessed and said rotating member is notched and ts in said recess, and said connecting means between said members comprises a spring pressed pin slidable radially in said normally stationary member and having a head at its outer end, and a selectively positioned cam slidable in said support and normally seating under said head.

9. The combination defined in claim 6, wherein said drive connection between said rotating and rotatable members is effected by a spring pressed pin carried by said rotatable member, a pair of cams slidably carried by said support in diametrically opposed relation to said rotatable member, one of said cams being normally projected in the path of said pin and the other being retracted, and means carried by said supports for shifting said cams to reversed positions to release said pin from one cam for engagement with said rotating member while the rotatable member rotates a half revolution to effect engagement of said pin with the other cam.

GEORGE L. GARVIN. 

